'Dirty Grandpa' trivia and fun facts

Jeff Bridges and Michael Douglas were considered for the role of Dick Kelly before Robert De Niro was cast.

For the naked motorcycle ride scene, Zac Efron used a body double.

Zac Efron in 'Neighbors' (2014) dressed up as Robert De Niro's "Travis Bickle" character in Taxi Driver (1976).

This is the second time that Robert De Niro has played a man in drag, after 'Stardust' (2007).

This is the second time that Zac Efron has played a character named Jason, after 'That Awkward Moment' (2014).

The first poster art for the movie references the famous film poster used for 'The Graduate' (1967).

The "Florida" spring break beach shown in the film is, in reality, Tybee Island in Georgia.

The screenplay for this film was featured in the 2011 Blacklist, a list of the "most liked" unmade scripts of the year.